Integrations of automatic theorem provers in proof assistants -- in the form of "hammers" -- are useful to formalize arbitrary mathematics. I will briefly talk about the experience we have with Sledgehammer and then focus on two ongoing project in which I am involved and a future one (modulo funding): automation of higher-order logic (Matryoshka); model finding for counterexample generation (Nunchaku); and formalization of number theory together with a mathematician.